The usual oxy cutting torch which is presently employed in industry utilises a nozzle having a central orifice through which oxygen passes, surrounded by a first row of orifices through which a combustible mixture of oxygen and acetylene gas flows, itself still further surrounded by a further row of outer apertures which will contain further oxygen. The combustible gases are mixed internally within the torch with much turbulence to assure thorough mixing, and this turbulent gas issues in small paralleljets. This co-operates with a turbulent oxygen stream which issues from a central oxygen jet within the combustible gas flame, and when excess oxygen is present, metal to be cut is burned.
One of the characteristics of this type of cutting torch is the presence of very turbulent gas at the cutting zone, this resulting in a rough cut surface and also in much burning of the parent metal, but this latter feature is most undesirable since quite often it is important that the edge should be as clean as possible.
In Australian Pat. No. 460,066, the applicant herein disclosed a welding torch attachment having its mixing chamber length at least eight times its diameter, and that diameter at least three times the nozzle aperture diameter. The attachment described in that Patent has proved commercially successful, mainly for the reason that the flame burns non-turbulent gases, resulting in a high temperature over a smaller area. This phenomenon has made it possible to weld metals which are not otherwise readily weldable.
One object of this invention is to provide improvements which will reduce the burning of the parent metal in an oxy cutting torch, and to take advantage of the high temperature concentrated heat available from the burning of non-turbulent gases.